N°177979 · Family detail
NikonWide·NIKON F mount·1977
Nikon AI Nikkor 20mm F/4
Specifications01
MountNIKON F
Focal length20mm
Max aperturef/4
TypeWide · Prime
Release year1977
Weight210 g
Filter size52 mm
Min focus distance0.3 m
Aperture blades7
Optical elements10
Groups8
AutofocusNo
StabilizationNo
Aperture controlAperture ring (Manual settings only)
Lens hoodHN-14 - Screw-type round
HK-3 - Clamp-on round
TeleconvertersNot compatible
EraFilm era
Production statusDiscontinued
Additional Info02
ModelAi
SeriesNikkor
Lens TypeUltra-wide angle prime lens
Iris Blades7
Focus Rotation Deg140
Field Notes02
Nikon F-mount 20mm fixed focal length lens with maximum aperture f/4, designed for wide-angle use such as landscapes and architecture. Manual-focus, non-extreme-wide perspective.
AI-assisted summary — verify against linked sources
Other Mounts03
No alternate mounts are indexed for this family yet.